Minimally invasive surgical (MIS) instruments are often preferred over traditional open surgical devices due to the reduced post-operative recovery time and minimal scarring. Laparoscopic surgery is one type of MIS procedure in which one or more small incisions are formed in the abdomen and a trocar is inserted through the incision to form a pathway that provides access to the abdominal cavity. The trocar is used to introduce various instruments and tools into the abdominal cavity, as well as to provide insufflation to elevate the abdominal wall above the organs. The instruments and tools can be used to engage and/or treat tissue in a number of ways to achieve a diagnostic or therapeutic effect. Endoscopic surgery is another type of MIS procedure in which elongate flexible shafts are introduced into the body through a natural orifice.
Various robotic systems have been developed to assist in MIS procedures. Robotic systems can allow for more intuitive hand movements by maintaining both natural eye-hand axis. Robotic systems can also allow for more degrees of freedom in movement by including a “wrist” joint on the instrument, creating a more natural hand-like articulation. One drawback with robotic systems, however, is that it can be difficult for the robotic systems to securely grasp, and therefore accurately move, instruments of different sizes. Since different instruments have different sizes, e.g., different shaft diameters, the robotic system may not be able to be used with certain instruments due to their size being too large or too small to be grasped by the robotic system and/or the robotic system may not be able to securely grasp some instruments as well as other instruments and thus be unable to move some instruments as accurately as other instruments. Even small instrument movement errors can cause any number of adverse effects during surgery, such as interference with other instruments, visual obstruction of other instruments and/or patient anatomy, and/or patient injury.
Accordingly, there remains a need for improved methods, systems, and devices for moving a surgical instrument coupled to a robotic surgical system.